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  • Open access
  • 69 Reads
meso-Triphenylamine-BODIPY derivative for optical chemosensing of metal ions

The design and synthesis of organic molecules for recognition of biologically/environmentally important metal ions have been emerging as a highly regarded research field. BODIPY core is a versatile signaling molecule that can be fine-tuned with functional groups to create binding sites and improve its optical properties. As an extension of the work developed in our research group, we report the synthesis and characterization of a BODIPY functionalized with triphenylamino and a formyl group at meso and 2-position, respectively, for a highly sensitive detection of Cu2+ and Fe3+. The preliminary study of the BODIPY derivative as optical chemosensor was carried out in acetonitrile solution in the presence of different cations and interaction with Cu2+ and Fe3+ induced a perceptible color change. The spectrophotometric titrations showed changes in the absorption spectra upon addition of 3 equivalents of each cation with the appearance of a new absorption band at 693 nm.

  • Open access
  • 67 Reads
Synthesis and characterization of a meso-anthracene-BODIPY derivative for colorimetric recognition of Cu2+ and Fe3+

Ions exist widely in biological and environmental media, and the scarcity or excess of these species can have adverse consequences for these media. BODIPY dyes appear as heterocyclic organic compounds capable of recognizing metal ions in solution and in cells, through optical signals (colorimetric and/or fluorimetric), and its photophysical properties can be adjusted through the functionalization of the BODIPY core. In continuation of the work developed recently, our research group reports the synthesis of a meso-anthracene-BODIPY derivative and the respective characterization by 1H and 13C nuclear magnetic resonance (NMR) and UV-Vis. spectroscopies. The preliminary study of the chemosensory capacity of the BODIPY derivative was also carried out in the presence of several cations in acetonitrile solution which shows a selective colorimetric response for Cu2+ and Fe3+.

  • Open access
  • 71 Reads
Uncommon coordination modes of a potential heptadentate aminophenol donor

This work describes the synthesis, characterization and reactivity towards HoIII of a potential heptadentate N4O3 aminophenol donor. The crystal structure of the [Ho(1,1,4-H3L)(1,1,4-H6L)] complex (1,1,4-H6L = 6,6'-(2-(5-bromo-2-hydroxy -3-nitrobenzyl)-2,5,8,11-tetraazadodecane-1,12-diyl)bis(4-bromo-2-nitrophenol)) shows that the holmium atom binds two aminophenol ligands, one acting as trianionic hexadentate, and the other one as neutral monodentate. As far as we know, both coordination modes of the aminophenol are hitherto unknown for this kind of scarcely reported ligand. This leads to a coordination number of 7 for the HoIII ion, which is in a capped trigonal prism environment.

  • Open access
  • 157 Reads
Main allergens in European hornet (Vespa crabo Linnaeus, 1758 ) and Asian hornet (Vespa velutina Lepetelier, 1836): a comparative study of their structural properties

The yellow-legged Asian hornet, (Vespa velutina Lepetelier, 1836), native to Southeast Asia, India, and China, has been accidentally introduced into South Korea in 2003 and France in 2004. The spread of the invasive hornet throughout Europe has been very rapid, resulting in frequent stinging incidents. Various studies have been carried out on the nature of the protein components of the Vespidae venom. It has been found that the allergens of Vespa velutina (VV), the European hornet (Vespa crabo Linnaeus, 1758 and the common wasp (Vespula spp) have a high similarity in their main proteins.

The structures generated by homology-modelling for the antigen 5 (Vesp v 5) from Asian hornet together with the main allergens from European hornet (Ves c 5.01 and Ves c 5.02), were studied using APBS (Adaptive Poisson-Boltzmann Solver), a continuum solvation method. The results obtained joined to another parameters calculated such as: LogP, vLogp, Molecular Lipophilicity Potential, among others, allows, not only, to check the high degree of similarity among these proteins but also, some differences that make possible the analysis of their epitopes. The obtained information could be useful in the characterization of Hymenoptera venom allergy (HVA) as well as for specific immunotherapy (SIT), since knowledge of the structure of allergens is essential for the precise diagnosis and treatment of HVA.

  • Open access
  • 60 Reads
Photosynthesis-Inhibiting Activity of Methoxy-substituted 3-Hydroxynaphthalene-2-carboxanilides

In this study a series of six 3-hydroxynaphthalene-2-carboxanilides, substituted on the anilide ring by combinations of methoxy-methoxy, methoxy-fluoro and methoxy-chloro groups at different positions, was prepared by microwave-assisted synthesis and characterized. The compounds were tested for their activity related to the inhibition of photosynthetic electron transport (PET) in spinach (Spinacia oleracea L.) chloroplasts. The PET-inhibiting activity of the compounds was within a wide range, but rather moderate; the highest activity within the series of the compounds was determined for N-(3,5-dimehoxyphenyl)-3-hydroxynaphthalene-2-carboxamide (IC50 = 24.5 µM). The compounds were found to inhibit PET in photosystem II.

  • Open access
  • 151 Reads
Evaluation of Phytochemical & Antimitotic Potential of Annona Reticulata extracts by Onion root model

This study investigated phytochemial investigation and extraction methods with polar and non polar solvent which could be used to compare and see the effectiveness of each on the chromosomes. The FTIR spectrum shows the presence of acetogenins in the extracts. Cytotoxic effects were studied using Allium cepa root tip cells. Eight onion bulbs were subjected to the treatment groups which were made using water, methanol, Ethyl acetate, acetone and hexane extracts of A. reticulata. Three different concentrations from each extraction solvent were used. The A. cepa root tip cells were subjected for 24 h to three different leaf extractions after left to grow in water. Concentrations of 0.1, 1, 10 and 50 mg/L were used. All studied concentrations of A. reticulata methanol extract showed significant (p˂0.05) drop in the mean mitotic index when compared with control Overall decrease in MI was contributed to by all the stages of mitosis.

  • Open access
  • 74 Reads
Cumulative Cytotoxicity Assay of the Aqueous and Ethanolic Extracts of the Selected Medicinal Plants using Crown Gall Tumor Disc Bioassay

The present study was conducted to test for in vivo crown gall tumor disc bioassay using potato discs of the aqueous and ethanolic extracts of Annona reticulata with Allium sativum, Allium fistolisum Brassica oleraceae and correlate cytotoxicity results with known pharmacological activities of the plants. Cytotoxicity was evaluated in terms of Crown Gall Tumor Disc Bioassay. The use of highly specific, quantitative bioassays which require only a short period of time to obtain results are available for studying crown gall tumor formation. Results showed that the extracts of Annona reticulata with Allium sativum, Allium fistolisum and Brassica oleraceae were potent against the Crown Gall Tumor Disc Bioassay when compared alone with combined extracts. It indicated that bioactive components are present in these plants that could be accounted for its pharmacological effects. Thus, the results support the uses of these plant species in traditional medicine.

  • Open access
  • 63 Reads
Study of ADMET Descriptors of Novel Chlorinated N-Arylcinnamamides

A series of seven (2E)-3-(3,4-dichlorophenyl)-N-arylprop-2-enamide were prepared. Six compounds from this limited set were mono- and di-chlorinated not only on the aromatic ring of acid but also on the anilide ring. The compounds have been proposed as potential anti-infective, anti-inflammatory and anti-cancer agents. Since lipophilicity significantly affects the biological activities and pharmacokinetic profile of the compounds, the hydro-lipophilic properties of these new highly chlorinated compounds were experimentally studied. At the same time, the overall ADMET profiles of the compounds were investigated if they comply with the Lipinski's Rule of Five and thus meet the qualitative concepts for the new bioactive molecules to be "druglikeness". All the discussed compounds were analysed using the reversed-phase high performance liquid chromatography method. The procedure was performed under isocratic conditions with methanol as an organic modifier in the mobile phase using an end-capped non-polar C18 stationary reversed-phase column. In the present study, the structure-lipophilicity relationships of the studied compounds are discussed.

  • Open access
  • 77 Reads
Synthesis of mono- and dinuclear cyclometallated compounds with palladium and platinum

Cyclometallated compounds, particularly with palladium and platinum, have been extensively studied over the past years in part due to their applications as catalysts in cross-coupling reactions. They are also useful in medicinal chemistry, and quite a large number have luminescent properties.

Herein, the synthesis and characterization of novel palladium cyclometallated compounds and a study of their reactivity with a diphosphine ligand is discussed. Mono- and dinuclear compounds were prepared depending on phosphine ligand coordination.

Characterization has been carried by IR spectroscopy, 1H and 31P NMR spectroscopy.

  • Open access
  • 75 Reads
Short and efficient first total synthesis of the natural product chromanone A, a chromone derivative from the algicolous marine fungus Penicillium sp.

In 2009, Gamal Eldeen et al. described the isolation and structural elucidation of chromanone A. This natural product is produced by a Penicillium sp., an endophyte isolated from the Egyptian green algae Ulva sp., grown in a solid medium with biomalt. The authors evaluated its chemopreventive activity against cancer (CYP1A inhibitor). Furthermore, the natural product was shown to possess potent hydroxyl and peroxyl radical scavenging activity.

In this work, we detail the first total synthesis of chromanone A in multiple stages from the inexpensive commercial product pyrocatechol and without the use of protecting groups.